Helicopter Sikorsky HRS-3 Serial 55-449 Register 137840 used by US Navy USN. Built 1953. Aircraft history and location Aircraft History 137840 US Navy 1953-06-05Sikorsky S-55 c/n 55-449, ff:? del USN as HRS-3, 137840, 05Jun53. Send Updates Use APP to upload photo @ (optional) When Now? / / Send
